Automobiles typically are provided with a variety of separate electrical systems, accessories, and options, resulting in the need for a substantial amount of wiring. The automotive industry is constantly seeking ways to reduce the amount, complexity and cost of this wiring in order to reduce the overall cost of producing an automobile.
With the introduction of junction box technology, the wiring of an automobile was simplified since the junction box provided a plurality of pre-wired circuits for centralized distribution of electrical signals to the various electrical systems and accessories. Likewise, the introduction of fuse or fuselink relay boxes simplified wiring by providing a centralized terminal for the fuses or fuselinks necessary to protect the various vehicle systems and circuits from current overloads.
Typically, a junction box (JB) is provided with its own corresponding fuselink relay box (FRB), and the JB and FRB are electrically connected by some sort of intermediate wiring. Prior art JB/FRB systems can generally be divided into two categories: those in which the fuselinks (FL) for the JB circuits are mounted on the FRB, and those in which the fuselinks for the JB circuits are fully incorporated in or mounted on the JB itself. A disadvantage inherent in the first category is the need for a plurality of intermediate wire connections between the fuselinks on the FRB and corresponding circuits on the JB. In view of the need for a reduction in the amount of wiring in the vehicle, this arrangement is less than ideal.
In the second category of prior art JB/FRB systems, in which the JB incorporates its own fuselinks, an additional busbar must be inserted or built into the JB to provide source current for the fuselinks, thereby increasing the size, complexity, and cost of manufacturing the JB. Additionally, a wire connection between the FRB and JB is still needed to supply current to the source busbar.
It is generally not practical to make the JB and FRB integral; i.e., to accommodate fuselink circuitry, wiring and other FRB structure in the JB in addition to the circuits already contained therein. Such addition would require a considerable increase in the size of the JB and in the complexity of manufacturing. Also, the heat generated by such a dense concentration of circuitry, wiring, busbars, fuselinks, etc., would be likely to damage the JB circuits.
In view of the need for a minimum of wiring in the electrical systems of vehicles, and in view of the disadvantages of prior art JB/FRB systems, it is therefore desirable to provide a JB/FRB system in which wire connection between the JB and FRB is eliminated without substantial increase in the size of complexity or the JB.